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Coulometrics User’s Manual
10
Weighing Carbonate Samples
Carbonate samples are weighed using the Cahn balance. The balance is connected to a Coulometrics balance program that records the sample mass, calculates a standard error for each
sample, and plots each mass graphically.
Start the balance program by double clicking on its icon. This opens the “Balance” window
(see Figure 14).
Figure 14. The “Balance” window.
Calibrating the Balance
Before samples are weighed, the Cahn balance must be calibrated. Calibrate the balance using
the Coulometrics balance progam. Two calibration are done during port call: 0-10 mg for Coulometer/CNS; 1-100 mg for RockEval. The balance should be calibrated with the hardware
first and then with the software.
Calibrating the Hardware
1. Set the Cahn balance to measure in the 250 mg to 1 microgram range.
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